fix high level for kwarg splatting

Author: ChrisRackauckas

test/high_level_solve.jl

@@ -8,22 +8,22 @@ using Distributions
 @test DiffEqBase.promote_tspan(Real[0,1.0]) == (0.0,1.0)
 
 prob = ODEProblem((u,p,t)->u,(p,t0)->p[1],(p)->(0.0,p[2]),(2.0,1.0))
-prob2 = DiffEqBase.get_concrete_problem(prob,nothing)
+prob2 = DiffEqBase.get_concrete_problem(prob)
 
 @test prob2.u0 == 2.0
 @test prob2.tspan == (0.0,1.0)
 
 prob = ODEProblem((u,p,t)->u,(p,t)->Normal(p,1),(0.0,1.0),1.0)
-prob2 = DiffEqBase.get_concrete_problem(prob,nothing)
+prob2 = DiffEqBase.get_concrete_problem(prob)
 @test typeof(prob2.u0) == Float64
 
 kwargs(; kw...) = kw
 prob = ODEProblem((u,p,t)->u,1.0,nothing)
-prob2 = DiffEqBase.get_concrete_problem(prob,kwargs(tspan=(1.2,3.4)))
+prob2 = DiffEqBase.get_concrete_problem(prob,tspan=(1.2,3.4))
 @test prob2.tspan === (1.2,3.4)
 
 prob = ODEProblem((u,p,t)->u,nothing,nothing)
-prob2 = DiffEqBase.get_concrete_problem(prob,kwargs(u0=1.01,tspan=(1.2,3.4)))
+prob2 = DiffEqBase.get_concrete_problem(prob,u0=1.01,tspan=(1.2,3.4))
 @test prob2.u0 === 1.01
 
 prob = ODEProblem((u,p,t)->u,1.0,(0,1))
@@ -34,7 +34,7 @@ prob = ODEProblem((u,p,t)->u,1.0,(0,1))
 
 prob = DDEProblem((u, h, p, t) -> - h(p, t - p[1]), (p, t0) -> p[2], (p, t) -> 0,
                   (p) -> (0.0, p[3]), (1.0, 2.0, 3.0); constant_lags = (p) -> [p[1]])
-prob2 = DiffEqBase.get_concrete_problem(prob, nothing)
+prob2 = DiffEqBase.get_concrete_problem(prob)
 
 @test prob2.u0 == 2.0
 @test prob2.tspan == (0.0, 3.0)